Gastric Atrophy and Intestinal Metaplasia before and after Helicobacter pylori Eradication: A Meta-Analysis

OBJECTIVE: Whether gastric atrophy (GA) and intestinal metaplasia (IM) are reversible after the eradication of Helicobacter pylori remains controversial. The purpose of this meta-analysis was to systematically review histological alterations in GA and IM by comparing histological scores before and after H. pylori eradication. METHODS: English-language articles in the medical literature containing information about the association between infection with H. pylori and gastric premalignant lesions (i.e. GA and IM) were identified by searching the Medline, PubMed, and EMBASE databases with suitable key words up to December 2009. Review Manager 4.2.8 was used for the meta-analysis. RESULTS: Twelve studies containing a total of 2,658 patients were included in the first meta-analysis. Before treatment, 2,648 patients had antrum GA, 2,401 patients had corpus GA, 2,582 patients had antrum IM, and 2,460 patients had corpus IM. Comparing the histological alterations before and after H. pylori eradication, the pooled weighted mean difference (WMD) with 95% CI for antral GA was 0.12 (0.00-0.23), p = 0.06. For corpus GA, the pooled WMD was 0.32 (0.09-0.54), p = 0.006. For antral IM, the pooled WMD was 0.02 (-0.12-0.16), p = 0.76, and for corpus IM, the pooled WMD was -0.02 (-0.05-0.02), p = 0.42. CONCLUSION: Our study shows that eradication of H. pylori results in significant improvement in GA in the corpus but not in the antrum; it also does not improve gastric mucous IM. Consequently, all patients with GA in the corpus should be tested for H. pylori infection, and eradication therapy should be prescribed for H. pylori-positive patients in those with GA in corpus.